Xpatrat plus 9x plus 8 egal 0

Răspuns :

x^2+x+8x+8=0
x*(x+1)+8*(x+1)=0
(x+8)*(x+1)=0
--> x= -1
x= -8
[tex]x^2+9x+8 = 0 \Rightarrow x^2+x+8x+8 = 0 \Rightarrow x(x+1)+8(x+1) = 0 \Rightarrow \\ \Rightarrow (x+1)(x+8) = 0 \Rightarrow x_1 = -1} , $ $ x_2 = -8[/tex]